Abstract: Disclosed herein are inhalation devices and methods for storage and release of substances in powder form such as a drug. The inhalation devices can include a plurality of powder chambers for storing a respective dose of a preloaded powdery substance, and an uncovering device for dispensing one dose at a time. The inhalation devices can include an advancing mechanism is arranged to feed the dose ring one powder chamber at a time. The powder chambers can be oriented in the surface of the dose ring and at least one seal is arranged to seal the powder chambers. The powder chambers can be uncovered or opened to at least a portion of an air channel, and the content of the powder chamber is exposed to, and can pass through, the air channel by means of an air flow.